Can I use the same Delta voucher for more than one ticket?

I have two Delta vouchers that are worth $400 each. I want to fly home with my kids and husband to see the grandparents, only I want to stay for about 3 weeks and my husband can only get time off for 6 days. Is it possible to buy three tickets (one having a different return date) in the same transaction with these vouchers?|||We could all give you our thoughts - BUT vouchers and free tickets rules change so often that the best person to check with - is the airline themselves.